Home Cosmetic Science Talk Formulating Hair Making a shampoo concentrate for dilution

  • Making a shampoo concentrate for dilution

    Posted by Annyeap on February 7, 2025 at 9:05 pm

    currently this business that i am helping out in makes a concentrate then they can just do a simple dilution, add fragrance/PQ-7 and then thicken it with salt solution when they have an order. At the moment the formulation being used, for a 2.5x dilution.

    Water QS

    SLES (70%) 28.8%

    CAPB (30%) 6%

    PRESERVATIVE

    Salt 1%

    The foam isnt good as after the dilution the SLES percentage is rather low. If i increase the percentage of SLES in the concentrate it makes it very difficult to dissolve and it is very thick? How can i increase the SLES percentage at this concentrate stage so i can still do a 2.5x dilution and have better foam?

    • This discussion was modified 1 month ago by  Annyeap.
    Richard replied 3 weeks, 5 days ago 3 Members · 8 Replies
  • 8 Replies
  • PhilGeis

    Member
    February 8, 2025 at 10:18 am

    This is not a good idea. Water is the single most significant source of contamination in manufacturing, and we take great pains to maintain its microbiological and chemical purity. However, we don’t have this with most tap water that typically includes pseudomonads like Pseudomonas aeruginosa - one of the most common causes of cosmetic recalls.

    This practice applied in hospitals has resulted ion the deaths of vulnerable folks. https://academic.oup.com/jid/article-abstract/158/3/655/2190564

  • Richard

    Member
    February 9, 2025 at 12:08 am

    I would say your SLES level is ok, I would increase the Betaine, through trials that you can run, to somewhere north of 20%. Remove the salt and add that later. Make sure whatever preservative you are using is 2.5 times higher than the final product.

    • PhilGeis

      Member
      February 10, 2025 at 5:38 am

      Apologies Richard - I have to comment as this practice, assuming consumer dilution, will most certainly have consumers using contaminated products. For most, this will at worst cause some mild folliculitis, but for immunocompromised folks (~30% of our population) the risk is serious as noted above.

      No preservative will cover the risk of uncontrolled tap water. Recall our cosmetic preservatives are weak - they are not expected to achieve in a month the level of kill required of disinfectant in less than 10 minutes.

      • Annyeap

        Member
        February 10, 2025 at 7:26 pm

        Hi Philgeis, this concentrate is not for consumer dilution. The concentrate is just for me to have a base that i can use if my customer wants different fragrances functions etc. I have a base i can dilute and add the relevant ingredients later on which makes dilution easier. So it will still be in a manufacturing facility with proper GMP controls.

    • Annyeap

      Member
      February 10, 2025 at 7:32 pm

      Thank you for your comment. I tried increasing CAPB and can get better foaming. Just the processing part gets more difficult because it is much thicker and makes stirring harder. I will have to find a way to improve the processing part.

      and yes, my preservative is calculated accordingly so when diluted it is at the correct amount.

      • Richard

        Member
        February 10, 2025 at 10:48 pm

        Yes I can see that will be a problem. Perhaps if you reduce both the SLES and Cocamidopropylbetaine and replace with a glucoside, but not Lauryl Glucoside. This will keep your foam level up and should not contribute to thickening of the base. But it will be trial and error and you will need to see how the end product performs in terms of thickening. I would start with 10% glucoside and removing 5% each of SLES and the betaine and see how that goes. And then you can go up or down.

        • Annyeap

          Member
          February 12, 2025 at 7:14 pm

          thanks for your suggestion Richard. i will give it a try. by any change do you know if SCI will help if i reduce some SLES and CAPB and add SCI instead. Will it still product a clear product that will thicken with salt?

          • Richard

            Member
            February 13, 2025 at 12:42 am

            SCI is not likely to thicken your product but in this system it is likely to be a problem at high levels, by going solid/white in the cold and clearer in the warm and also dropping out. I haven’t worked with these high levels before so I am only guessing, so I suggest you try it. But my preference remains a glucoside.

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